60 eligible subjects will be randomized into one of three study arms 1) aerobic exercise, 2) resistance exercise, or 3) usual care. Baseline measurements will be done on all study subjects, these measurements include: height, weight, dual energy x-ray absorptiometry (DXA) for bone mineral density and lean body mass measurements, blood will be taken to measure serum free testosterone, prostate-specific antigen (PSA), glucose, and insulin levels. Fitness will also be evaluated using a graded exercise test. Questionnaires on health and personal history will also be completed. Men randomized to the aerobic exercise treatment arm will participate in a walking program three times a week for eight weeks. The participants will start at 15 minutes per session and increase to a goal of 60 minutes per session. Men randomized to the resistance training treatment arm will participate in an eight-week program of eight strength training exercises three times per week. Men in the usual care arm will receive written materials from the American Cancer Society about coping with cancer, which includes information about participation in physical activity. At the end of the eight week intervention participants in all three study arms will complete the same questionnaires and measurements they completed at baseline.